public static EitherAsync <L, OptionAsync <B> > Sequence <L, A, B>(this OptionAsync <A> ta, Func <A, EitherAsync <L, B> > f) => ta.Map(f).Sequence();
public static TryAsync <OptionAsync <B> > Sequence <A, B>(this OptionAsync <A> ta, Func <A, TryAsync <B> > f) => ta.Map(f).Sequence();
public static ValueTask <OptionAsync <B> > Sequence <A, B>(this OptionAsync <A> ta, Func <A, ValueTask <B> > f) => ta.Map(f).Sequence();
public static OptionAsync <B> map <A, B>(OptionAsync <A> ma, Func <A, B> f) => ma.Map(f);
public static Aff <RT, OptionAsync <B> > Sequence <RT, A, B>(this OptionAsync <A> ta, Func <A, Aff <RT, B> > f) where RT : struct, HasCancel <RT> => ta.Map(f).Sequence();